In recent years, thin, light, and low-power-consumption display devices such as liquid crystal display devices have been widely used. It is noteworthy that such display devices have been mounted, for example, on mobile phones, smartphones, laptop PCs (personal computers), and the like. It is also expected that in the future, development and prevalence of electronic paper (which is even a thinner display device) will be rapidly advanced. Under such circumstances, it is now a common challenge to reduce power consumption of display devices.
Patent Literature 1 discloses a display device driving method that achieves low power consumption by allowing for a non-scanning period (i) which is longer than a scanning period in which a screen is scanned once and (ii) during which all scan signal lines are in a non-scanning state.
Meanwhile, a touch panel to be mounted as a display screen of such a display device has also been widely used (such as the touch panel disclosed in Patent Literature 2). The touch panel is a locator device that (i) detects a position on the display screen as specified by a user's finger, a pen, or the like (hereinafter referred to as “finger or the like”) and then (ii) outputs positional information indicative of the position thus detected. Since the touch panel allows more intuitive operations than does an input device such as a keyboard and a mouse, the touch panel has been notably mounted, for example, on a mobile phone, a smartphone, a tablet PC, or the like.